Toxins
-
Randomized Controlled Trial Multicenter Study
Cost-effectiveness of treating upper limb spasticity due to stroke with botulinum toxin type A: results from the botulinum toxin for the upper limb after stroke (BoTULS) trial.
Stroke imposes significant burdens on health services and society, and as such there is a growing need to assess the cost-effectiveness of stroke treatment to ensure maximum benefit is derived from limited resources. This study compared the cost-effectiveness of treating post-stroke upper limb spasticity with botulinum toxin type A plus an upper limb therapy programme against the therapy programme alone. ⋯ The probability of botulinum toxin type A plus therapy being cost-effective at the England and Wales cost-effectiveness threshold value of £20,000 per QALY was 0.36. The point estimates of the ICER remained above £20,000 per QALY for a range of sensitivity analyses, and the probability of botulinum toxin type A plus therapy being cost-effective at the threshold value did not exceed 0.39, regardless of the assumptions made.
-
Voltage-gated sodium channels (VGSC) are the primary mediators of electrical signal amplification and propagation in excitable cells. VGSC subtypes are diverse, with different biophysical and pharmacological properties, and varied tissue distribution. Altered VGSC expression and/or increased VGSC activity in sensory neurons is characteristic of inflammatory and neuropathic pain states. ⋯ To date, only the μ- and μO-family exhibit analgesic properties in animal pain models. This review will focus on conotoxins from the μ- and μO-families that act on neuronal VGSCs. Examples of how these conotoxins target various pharmacologically important neuronal ion channels, as well as potential problems with the development of drugs from conotoxins, will be discussed.
-
Human voltage-activated sodium (Nav) channels are adept at rapidly transmitting electrical signals across long distances in various excitable tissues. As such, they are amongst the most widely targeted ion channels by drugs and animal toxins. ⋯ Although the functional properties of Nav1.8 have been relatively well characterized, difficulties with expressing Nav1.9 in established heterologous systems limit our understanding of the gating properties and toxin pharmacology of this particular isoform. This review summarizes our current knowledge of the role of Nav1.8 and Nav1.9 in pain perception and elaborates on the approaches used to identify molecules capable of influencing their function.
-
Drug delivery of immunotoxins to brain tumors circumventing the blood brain barrier is a significant challenge. Convection-enhanced delivery (CED) circumvents the blood brain barrier through direct intracerebral application using a hydrostatic pressure gradient to percolate therapeutic compounds throughout the interstitial spaces of infiltrated brain and tumors. ⋯ Understanding this challenge, it is surprising that so little work has been done to monitor the delivery of therapeutic agents using this novel approach. Here we present a review of imaging in convection enhanced delivery monitoring of toxins in humans, and discuss future challenges in the field.
-
In a previous study, we used bacterial flagellin to deliver antigens such as p27 of Mycobacterium tuberculosis to a host immune system and obtained a potent Th1 response compared to those obtained with Freund's adjuvant and DNA immunization. In the current study, using a POMP91B antigen of Chlamydophila abortus, a human and animal pathogen, as a model, we found that this antigen is unable to promote Th1 response. However, this antigen, unlike others, was able to induce a good Th2 response and IL-4 production after immunization by recombinant protein in Freund's adjuvant or in phosphate buffered saline. Our results suggest that immune response is not only dependent on the immunization adjuvant, but also dependent on the nature of antigen used.